I really hope Kane gets a title shot if Rey isn't going to be able to go.
What they should do is have Rey jumped by Edge's posse backstage and show Edge laughing as Rey is being carted out on a stretcher and then have Theodore Long announce that Edge isn't out of the fire just yet, and he should announce Kane as his opponent.
Why?
It just seems to make sense.
Kane isn't booked for the event. Second, the Edge/Kane rivalry from the Summer is still unresolved and it'd be VERY, VERY easy for WWE to hotshot an angle with Kane and Edge since there's obviously a built in history between the two. Third, it makes for an interesting scenario because they can play up the irony how by injuring Edge months ago Kane screwed himself out of a one on one title match by accident. Now, all these months later, Kane gets a one on one title match because of another superstar's injury. Fourth, it makes it a little more interesting of teasing a Kane/Taker Wrestlemania main event and can add that little dynamic the whole night. If Taker wins the Chamber, like everyone thinks he will, then you can have a situation where if Kane takes the title, they could tease a Kane/Taker Mania title match. Sure, it won't happen, but it'd be much more interesting to tease that than Taker/Mysterio. Plus, beyond that, Kane can get his title shot and still lose due to interference from Ryder and Hawkins, and then, you can even have Shelton interfere to add a bit of fire to the Kane/Benjamin rivalry. Finally, Kane's over enough to be thrust into a title match at any time and still get a good reaction.
NOW, all that aside, if that doesn't happen, my guess is that the match will start and Edge will just have a squash and maybe they'll add Kane/Shelton to the card.